I have a 1996 F250 with the 5.8 EFI V8 that just developed an idle problem. After initial startup the engine runs smooth for about 5 seconds then goes into a loping condition. The Haynes repair manual I have suggests a vacuum leakage as one of several potential culprits so I started to check vacuum lines and connections for problems and found nothing obvious. But then, while the engine was loping along I disconnected one set of double line connectors on a black plastic container that looks like a small loaf of bread and the engine started to run smoothly. Wow, what a lucky shot in the dark that was.

This container is located on the right side (passenger side) of the engine compartment between the battery and the AC accumulator. It has 2 sets of double vacuum line connections on one end, one set above the other. The top pair is red and white in color and the bottom set is red and black in color. There is a Ford logo and number molded into the plastic top of this case, it's FOTE-9E453-AA and
PA6-M+G40. When I connect the top set of lines back on the engine loping resumes.

I can't find any reference to this thing in that Haynes service manual. Does anyone know what this container is and do you thing replacing it might solve the problem?

Thanks in advance.

 

There are two that come to my mind

1: The vacuum canister(Looks like a big tin juice can), this has two vacuum lines(I don't know where they lead off the top of my head)

2: The Charcoal canister(Should look like a rectangle, should have a line feeding from the gas tank to somewhere on the intake, I believe)

 

Well, I found the vacuum diagram stuck to the underside of the hood, whata-ya-know.... and the diagram indicates the canister is the vacuum reservoir. As I mentioned, when I pull off the red/white tubes (red goes to manifold vacuum tree, white to EGR sol valve) the engine idles smooth. When I pull of the black/red tubes from the vacuum reservoir (black goes to Air B/Air D sol valve, red to vac tree) the engine gets worse and almost dies. So..... could it possibly be the EGR Sol V alternatively to something wrong with the reservoir? I did notice when I pulled off the black/red tubes there was a sucking sound like a vacuum was lost. That didn't happen (that I noticed) when I pulled off the red/white tubes from the reservoir. Any more ideas anyone?